Tubular knitted fabrics

ABSTRACT

A CLOSED FABRIC TUBE AND METHOD OF FORMING IT IN WHICH A FIRST TUBULAR PORTION OF FABRIC IS KNITTED ON A KNITTING MACHINE AND, WHILST ITS LAST FORMED LOOPS ARE HELD, ANOTHER AND SEPARATE TUBULAR PORTION OF FABRIC IS FORMED ON THE MACHINE AND CLOSED BY CONSTRICTION, THE TWO PORTIONS OF FABRIC BEING AFTERWARDS JOINED BY AT LEAST ONE CONNECTING COURSE OF KNITTING. THE SEPARATE SECOND PORTION OF FABRIC MAY BE OF WELT-LIKE CONSTRUCTION AND CONSTRICTED AT THE FOLD OF THE WELT.

Dec. 14, 1971 P. M. FINDLAY ETAL 3,626,726

TUBULAR KNITTED FABRICS 2 Sheets-Sheet 1 Filed Nov. 19, 1968 Dec. 14, 1971 Filed Nov. 19, 1968 P. M. FINDLAY ET AL TUBULAR KNITTED FABRICS 2 Sheets-Sheet 2 United States Patent 3,626,726 TUBULAR KNITTED FABRICS Peter Michael Findlay, Forest East, William Ewart Alan Shelton, Oadby, and John Michael Klee, Leicester, England, assignors to The Bentley Engineering Company Limited, Leicester, England Filed Nov. 19, 1968, Ser. No. 776,943 Claims priority, application Great Britain, Nov. 22, 1967, 53,066/ 67 Int. Cl. D04b 9/56 US. Cl. 66-95 12 Claims ABSTRACT OF THE DISCLOSURE A closed fabric tube and method of forming it in which a first tubular portion of fabric is knitted on a knitting machine and, whilst its last formed loops are held, another and separate tubular portion of fabric is formed on the machine and closed by constriction, the two portions of fabric being afterwards joined by at least one connecting course of knitting. The separate second portion of fabric may be of welt-like construction and constricted at the fold of the welt.

This invention is for improvements relating to tubular knitted fabric and is concerned with the closure of a knitted tube whilst on the machine on which it is knitted, thereby avoiding the need for a subsequent closure operation. The invention has for an object to provide a convenient and effective way of closing a fabric tube in a case where the tube is first knitted and closure effected at the conclusion of the knitting of the tube.

In accordance with the invention there is provided a method of forming a closed fabric tube on a knitting machine in which a tubular portion of fabric is first knitted and then, whilst the last formed loops of the tube are held, another portion of fabric which constitutes the closure is formed on the machine and the two parts are subsequently joined by a connecting course or courses of knitting. The closed tubular article is thus formed in two parts on the same machine, the second part being formed whilst the first part is held and the joining of the parts being then effected on the machine. Conveniently the part which is to form the closure is knitted in the manner of a welt which is formed in two plies the crease or fold in the fabric between the plies being constricted in a convenient manner while the fabric is on the knitting machine in order to form a closure. The constriction may be effected by tightly wrapping or binding or by clenching the central part of the length of material forming the double ply fabric, or by turning one ply through at least 180 in relation to the other to form a twisted closure at the junction between the plies.

In practising the invention the operations of knitting the main part of the tubular fabric and knitting the piece of fabric to form a closure at its end follow one another, and Without releasing either piece of fabric from the machine contiguous parts of them are brought together on the needles and knitted to form a join between them. The knitting of anti-ravel courses completes and, so to speak, seals the join.

The invention is of particular use in connection with the knitting of stockings, socks and other articles of hosiery footwear and may conveniently be employed to form a toe closure at the conclusion of knitting of the foot part of the article.

In a convenient sequence the knitting procedure may be performed on a circular knitting machine as follows. After completing the knitting of the tubular fabric required to be closed, courses providing anti-run loops are knitted Patented Dec. 14, 1971 on all the needles and then alternate needles are caused to release their loops. The intervening needles are directed to a low inactive track in which they simply hold their loops using intervening welt hooks or other holding needles. The fabric for the toe end closure is then set up their loops thereby retaining the knitting tube on the and knitted on the alternate needles which have released instruments (aligned with the lowered needles) to hold the initial courses of the fabric while sufficient length of fabric is produced to form a centrally constricted double ply portion for the end closure. Constriction of the fabric is then caused by wrapping a binder round or clinching the fabric, or twisting the fabric by causing relative turning movement between the needles and holding instruments about the axis of the needle cylinder. The loops on the holding instruments are thereupon transferred to the aligned needles and all needles are brought into action to knit courses serving to join the plies of the end closure together and to the end of the tubular fabric. After this anti-ravel courses are knitted to complete the closure.

In an alternative procedure the end closure fabric may be knitted on alternate needles which hold loops of the last course of the tubular fabric on their stems at low level out of activity and after completing and constricting the closure portion its ends are knitted together and to the end part of the tubular fabric.

The invention includes a closed knitted fabric tube comprising a portion of tubular knitted fabric and a separately knitted closure part of tubular knitted structure constricted inwardly at one part to a substantially complete closure and joined at an open part to an end of said portion of tubular fabric by a separate knitted course of joining loops. The tubular knitted closure part may be folded centrally of its length to double ply structure and constricted inwardly at the fold to form the closure (for example by a binding yarn or equivalent means contained in the fold of the two ply closure), the first and last portions of the closure part being joined to the end of said portion of tubular fabric by said course of joining loops which may form part of a knitted band of run resistant fabric.

In practicing the invention a stocking may have at least the foot part formed by a knitted fabric tube provided with a separately knitted closure part as just referred to forming the toe end part of the foot.

Certain preferred procedure will now be described in detail with reference to the accompanying drawings in which:

FIG. 1 is a diagrammatic central cross-sectional elevation view of a needle cylinder and dial of a circular knitting machine illustrating the knitting procedure at one stage,

FIGS. 2 and 3 are corresponding views illustrating the knitting procedure at later stages, and

FIG. 4 is a somewhat diagrammatic view in cross section of a portion of a knitted fabric tube provided with a closure part forming the toe end of a stocking foot.

In the drawings the needle cylinder is shown at 10, the dial at 11, active needles at 12 slidable in tracks in the cylinder 10, lowered inactive needles at 12a, and welt hooks or other loop holding instruments (e.g. needles) at 13.

A stocking is knitted on the machine starting at the welt end, conveniently with a normal turned welt, and continuing through the panel or leg, the heel and the foot up to the toe end. Up to this point all of the needles are active and caused to operate in accordance with an orthodox procedure. Having knitted the final course of the foot, and with the stocking indicated at 14 dpending from ethis fiinal course, all of the needles are made to knit a course or a small number of courses of anti-run loops and then alternate needles are lowered and made to release their loops and then raised to an active level indicated at 12. The intermediate needles, which are the ones aligned with welt hooks (there being usually approximately half as many welt hooks as needles), are directed to a low inactive track and at this level are indicated at 12a and simply hold the stocking 14 by the remaining loops of the last non-run course.

A separate piece of fabric for the toe portion is now commenced on the empty alternate needles 12 and yarn from a feeder 16 is laid over the welt books 13 which are advanced above the low intermediate needles 12a. The sequence of knitting the initial make-up courses of the toe piece can follow known principles except that the intermediate needles 12a remain inoperative and holding the stocking as previously stated. After the make up, knitting is continued on only the alternate needles 12 with appropriate yarn changes to provide a portion of fabric 15, FIG. 1, of reduced density as compared with the fabric of the remainder of the stocking, having only half as many wales as the latter. The object of the reduced density is to minimise the bulk of the fabric at the zone to be constricted. Additionally, a variety of stitch reducing constructions may be employed to reduce still further the bulk of the fabric if desired. FIG. 1 illustrates this stage of the procedure.

Having completed the toe portion the alternate needles 12 are then directed to the low inoperative track at the levels of needles 12a (the stage illustrated in FIG. 2), whilst yarn 17 is furnished from a feeder 16 (which may be the same feeder as used for knitting the fabric 15) at the appropriate feed position to be wound around the the fabric to bind it together so as to provide the constriction to close the toe portion. The feeder 16 is positioned so that the yarn 17 is fed into a peripheral space between the tops of the needles and the welt hooks 13 which continue to hold the initial make-up course of the separate toe piece. The cylinder and the dial 11 carrying the welt hooks 13 are slightly separated to provide such a space. If the yarn 17 is additional to the yarn from which the toe portion fabric is knit, the feeder 16 is caused to feed its yarn to a small number of the alternate needles 12 while they are still knitting and before the feeder is moved to what may be termed a laying-in position as in FIG. 2. The yarn 17 is thereby knit into a few stitches of the fabric and will extend from the last needle which has knitted it (and to which it is attached) and be drawn around the outside of the fabric tube. Suitable tension is maintained on the yarn so fed to ensure tight wrapping of the fabric to give proper closure. While the yarn 17 is being supplied, knitting is stopped on the needles 12 which are kept in lowered position. Therefore the effect is that the laid-in yarn 17 will simply be wound around the short fabric tube extending from the welt hooks 13 to the needles 12. If sufficient tension is put on the yarn 17 it will draw the fabric tube into a closed neck by constricting that part of the fabric which is about equidistant between the welt hooks 13 and the needles 12. With each successive revolution of the cylinder and dial, a successive turn of yarn will be obtained around the neck of the fabric. When a desired number of turns has been made, the feeder 16 is moved from the laying-in position to the knitting position so that its yarn is again taken by the needles 12 which are raised to receive it. Thus the wrapping yarn is locked into the fabric. Alternatively closure may be effected by turning the cylinder 10 through upwards of 180 and preferably 360 relatively to the dial 11 at this stage, as described in US. Patent No. 3,340,706.

The toe piece fabric is now joined to the main fabric 14 of the foot by projecting the dial jacks above the low intermediate needles which have been holding the stocking and raising these needles to receive the loops from the dial jacks. The actual closing of the toe is preformed by retracting the jacks as shown in FIG. 3 and knitting on all needles for a few courses an anti-rave] fabric tab, after which the stocking is released from the needles.

In an alternative procedure knitting of the welt, leg,

heel and foot parts is carried out as above and then im mediately before the stage illustrated in FIG. 1 all needles are lowered to an inactive level and without knitting any anti-run fabric at this time alternate needles which aligned with the welt hooks 13 are held down out of action whilst intervening needles are raised as at 12 into activity whilst still holding at low level the loops last formed on them. The retention of such loops at low level may be assisted by the use of sinkers having two throats and two draw platform at different levels and staggered appropriately in the direction radially of the cylinder as disclosed in British patent specification No. 1,129,983 published Oct. 9, 1968. Then the separate fabric 15 is commenced by make up courses formed on the active needles 12 with the aid of the welt hooks 13 which hold the start of the fresh fabric 15.

The situation at this stage which is like that illustrated in FIG. 1 is as follows. The stocking, completed except for the toe portion, is held at a low level on all needles. A separate piece of fabric 15 has been commenced on intermediate needles only at the normal level in conjunction with the welt hooks 13 which are projected over the low alternate needles. This separate piece of fabric 13 may be commenced in much the same way as a conventional inturned welt but using only the intermediate needles throughout the make-up and the subsequent knitting of the separate piece. As knitting proceeds the fabric will form a loop or fold between the dial hooks 13 and the needle circle 12, the said fabric being produced as shown in FIGS. 1 and 2 above the fabric 14- of the stocking proper which is depending from the needles 12a. At the appropriate time the fold of fabric is constricted to form a closure of the tube midway between the hooks and the needles as already described.

Finally, the loops are transferred from the welt hook 13 back to the alternate needles 12a which are raised to receive them, and the loops which have been at low level are knitted in with the loops at a higher level on all of the needles. This action causes the separately knitted fabric toe portion 15 to be joined to the stocking 14 at all needle wales. Knitting then takes place on all needles in an anti-run sequence to enable the completed hose to be pressed off the needles.

In both procedures just described the toe closure fabric is knitted with only half the number of wales in the fabric knitted before the closure position thereby reducing the bulk of the fabric at the place of constriction. This bulk may be reduced still further by knitting with a suitably varied fabric structure (e.g. a tuck stitch or missed stitch structure) at or near the position of constriction or by substituting a thinner yarn than that previously used at such position.

The machine elements by which the welt like fabric providing an end closure to the fabric tube is formed are controlled by machine control means which is largely of orthodox type. The lowering of the needles when required, the movement into and out of action of the feeder 16 by which the constricting yarn is supplied, the projection and withdrawal of the welt dial hooks 13, and the actuation of other machine part movements are effected by instrumentalities brought into action in correctly timed sequence from a main control drum or other equivalent part which is caused to move in steps conveniently by impulses derived from patterning means (e.g. a chain with projections) which is itself moved step by step at regular or other appropriate intervals related to the working of the machine.

It will be evident that the procedure described above can be performed on a dial and cylinder knitting machine having needles instead of welt hooks in the dial, and also on an opposed needle cylinder type of machine in which case needles transferred to the top cylinder would operate as holding elements in place of the welt hooks.

FIG. 4 shows diagrammatically in cross section a portion of a fabric tube provided with a separately knitted closure part in accordance with the procedure herein described. The fabric and closure part are shown as a footpart and toe end part of a stocking or other article of knitted hosiery footwear and are indicated respectively at 14 and 15 as being the items bearing these reference numbers in the earlier figures. It will be seen that the separately knitted closure part 15 is of tubular knitted structure which has been folded centrally of its length to double ply structure and constricted inwardly at one part, being the fold of the double ply structure, to form the closure by means of the wrapping yarn 17. This is coiled as indicated at 17a to constrict the fold to a substantially closed condition at the point 18. The closure part 15 is joined at its open ends to an end of the fabric portion 14 by a separate knitted course of joining loops along the line 19 serving to join the first and last portions of the closure part 15 to the end of the fabric part 14, The separate knitted course of joining loops along the line 19 forms part of a knitted band of run-resistant fabric indicated at 20 serving to finish the knitted structure and permit it to be cast off the needles. When formed by the first method described with reference to FIGS. 1 to 3, a small band 21 of run resistant fabric is formed at the end of the fabric tube 14 adjacent to the join line 19. The band 21 is however not present when the alternative method of procedure is used.

What we claim is:

1. A method of forming a closed fabric tube on a circular knitting machine having a circular series of needles comprising the steps of knitting a first tubular portion of fabric on needles of the machine, holding said first tubular portion on spaced needles of said series interspersed between other needles of said series, knitting a second and separate tubular portion of fabric on said other needles of said series whilst holding the last formed loops of the said first tubular portion on said spaced needles, closing said second tubular portion, and subsequently joining said first and second tubular portions by at least one connecting course of knitting knitted on said spaced needles and said other needles.

2. A method according to claim 1 comprising knitting said second tubular portion of fabric in the manner of a welt with two plies and a fold in the. fabric between the plies, and closing said second portion by constricting the fabric at the fold in the fabric between the plies.

3. A method according to claim 2 wherein the constricting of the second tubular portion of fabric is effected by tightly binding the central part of the length of material forming the two plies.

4. A method according to claim 2 wherein the constricting of the second tubular portion of fabric is effected by twisting one ply in relation to the other to form a twisted closure.

5. A method according to claim 1 comprising the further step of knitting a band of run-resistant fabric as a continuation from the iunction between the first and second tubular portions of the fabric.

6. A method according to claim 1 wherein the said second and se arate tubular portion of fabric is knitted on fewer needles than those used for knitting the first tubular portion of fabric.

7. A method according to claim 6 wherein, after knitting the first tubular nortion of fabric, courses providing anti-run loops are knitted on all the needles consisting of said spaced needles and said other needles, and then said other needles are caused to release their loops, said spaced needles are directed to a low inactive track to hold the first portion of fabric, and the second portion of fabric is then set up and knitted on said other needles which have released their loops, using intervening welt holding instruments to hold the initial courses of the second portion of fabric while a suflicient length of said second portion of fabric is produced.

8. A method according to claim 6 wherein, on completion of the first tubular portion of fabric, the last course of loops thereof is held at low level with said spaced needles lowered and said other needles raised to knit the second tubular portion of fabric at a higher level using intervening welt holding instruments to hold the intial courses of the second portion of fabric while a sufiicient length of said second portion of fabric is produced, the first and last courses of the second portion of fabric being subsequently knitted in with the last course of loops of the first tubular portion of fabric that have been held at low level.

9. A method according to claim 1 wherein said first tubular portion of fabric comprises the leg and foot portion of an article of hosiery footwear and said second tubular portion of fabric comprises a toe portion of said article.

10. A method of knitting an article of hosiery footwear having leg, foot and toe portions which comprises knitting on a circular knitting machine having a circular series of needles a plurality of courses to form a first tubular portion of fabric comprising a leg and foot portion of said article, holding a terminal course of said first portion of fabric on spaced needles of said series which are kept inactive while knitting a plurality of courses on intervening needles of said series to form a second and separate tubular portion of fabric comprising a toe portion of said article, an initial course of said second portion of fabric being held by welt holding instrumentalities while said second portion of fabric is being knit, constricting a central portion of said second portion of fabric to effect a closure thereof, and knitting at least one course on said spaced needles and intervening needles to join an initial course and terminal course of said second portion of fabric with a terminal course of said first portion of fabric.

11. A method according to claim 10 wherein said constricting of said second tubular portion of fabric is effected by wrapping a yarn around a central portion of said fabric.

12. A method according to claim 11 wherein end portions of said wrapping yarn are secured by being knitted into the fabric.

References Cited UNITED STATES PATENTS 1,188,125 6/1916 Williams. 1,211,021 1/1917 Williams 66-148 1,270,083 6/1918 Williams 66-187 1,270,084 6/ 1918 Williams 66-95 X 1,533,868 4/1925 Kingman. 1,738,787 12/1929 Miller 66-187 X 2,020,556 11/ 1935 Kirkpatrick 66-1 2,069,021 1/ 1937 Schuessler 66-171 2,150,335 3/1939 Miller et al. 66-173 2,292,231 =8/ 1942 Lesavoy. 2,408,807 10/ 1946 Norman 66-1 2,522,842 9/ 1950 Scholl. 2,601,771 1/1952 Cameron 66-170 2,63 6,492 4/1953 Wright 2-21 X 3,184,236 5/1965 Zens. 3,254,509 6/ 1966 Tenconi 66-41 3,301,012 1/1967 Tenconi 66-41 3,340,706 9/ 1967 Currier.

FOREIGN PATENTS 697,859 11/1964 Canada. 865,092 4/ 1961 'Great Britain.

OTHER REFERENCES The Hosiery Trade Journal, November 1966, p. 129.

WM. CARTER REYNOLDS, Primary Examiner US. Cl. X.R. 66-170, 187 

